Accurate three-step algorithm for joint source position and propagation speed estimation

A popular strategy for source localization is to utilize the measured differences in arrival times of the source signal at multiple pairs of receivers. Most of the time-difference-of-arrival (TDOA) based algorithms in the literature assume that the signal transmission speed is known which is valid for in-air propagation. However, for in-solid scenarios such as seismic and tangible acoustic interface applications, the signal propagation speed is unknown. In this paper, we exploit the ideas in the two-step weighted least squares method [1] to design a three-step algorithm for joint source position and propagation speed estimation. Simulation results are included to contrast the proposed estimator with the linear least squares scheme as well as Cramér–Rao lower bound.